1. Field of the Invention
The subject invention is directed to implantable cardiac leads, and more particularly, to an implantable cardiac lead having a removable connector port for facilitating the introduction of an optical imaging fluid or therapeutic agent into a fluid delivery lumen extending through the lead body.
2. Background of the Related Art
Implantable cardiac stimulation leads, including epicardial and endocardial leads, are well known in the art. In general, these devices have an elongated flexible body with an electrode assembly at one end for contacting and stimulating cardiac tissue and a connector assembly at the other end for mating with an automated stimulation device, such as a pacemaker or defibrillator. The distal end of the lead can include a helical screw to facilitate active fixation of the lead tip or a plurality of flexible tines to facilitate passive fixation of the lead tip.
The implantation of a cardiac lead is often performed under vision with the aide of an imaging process such as fluoroscopy, angiography or optical densitometry using an optical contrast agent or dye. These imaging fluids are typically introduced to the lead implantation site by way of a catheter. For example, U.S. Pat. No. 6,540,765 to Malacoff discloses an apparatus for placing a pacing electrode in the coronary sinus of the heart which is defined by a catheter having a central lumen through which a lead is advanced for placement. A Tuohy-Borst multi-port adapter is provided at the proximal end of the catheter for receiving a dye. Once injected into the adapter, the dye travels through the lumen of the catheter into the coronary sinus through an exit port in the distal end of the catheter, and periodic angiograms are performed to assist in the proper placement of the lead.
The use of a catheter to facilitate the delivery of an optical imaging fluid such as a contrast agent or dye is not particularly cost effective and generally adds to the overall complexity of the lead implantation procedure. It would be beneficial therefore, to provide an implantable cardiac lead that is adapted and configured to effectuate the delivery of an optical imaging fluid to the site of lead implantation, without the, need of a catheter or similar assisting device.